add release instructions

docs/release-pipi.md

@@ -0,0 +1,33 @@
+# Release instructions 
+
+Using twine : https://twine.readthedocs.io/en/latest/ 
+
+1. Update the `__version__` in `mtdata/__init__.py`  
+   Clear `rm -r build dist *.egg-info`   if those dir exist.
+2. Build :: `$ python setup.py sdist bdist_wheel`   
+   where `sdist` is source code; `bdist_wheel` is universal ie. for all platforms
+3.  Make docs: `docs/make-docs.sh`
+4. Upload to **testpypi** ::  `$ twine upload -r testpypi dist/*`
+5. Upload to **pypi** ::  `$ twine upload -r pypi dist/*`
+
+
+### The `.pypirc` file
+
+The rc file `~/.pypirc` should have something like this 
+```ini
+[distutils]
+index-servers =
+    pypi
+    testpypi
+
+[pypi]
+repository: https://upload.pypi.org/legacy/
+username:Thamme.Gowda
+password:<password_here>
+
+
+[testpypi]
+repository: https://test.pypi.org/legacy/
+username:Thamme.Gowda
+password:<password_here>
+```